13991904 has 72 divisors (see below), whose sum is σ = 41900040. Its totient is φ = 4416768.

The previous prime is 13991897. The next prime is 13991911. The reversal of 13991904 is 40919931.

It is an interprime number because it is at equal distance from previous prime (13991897) and next prime (13991911).

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4194 + ... + 6750.

It is an arithmetic number, because the mean of its divisors is an integer number (581945).

Almost surely, 2^13991904 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13991904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20950020).

13991904 is an abundant number, since it is smaller than the sum of its proper divisors (27908136).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13991904 is a wasteful number, since it uses less digits than its factorization.

13991904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2592 (or 2581 counting only the distinct ones).

The product of its (nonzero) digits is 8748, while the sum is 36.

The square root of 13991904 is about 3740.5753568134. The cubic root of 13991904 is about 240.9677590979.

The spelling of 13991904 in words is "thirteen million, nine hundred ninety-one thousand, nine hundred four".